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Constrained Route parameters

By default your route parameters are assumed to be strings.

If you know you’re expecting something else (like an int) you can constrain your route parameter to this type.

So long as you declare a corresponding parameter in your code (with the same name and type) you’ll be guaranteed that int.

// this constrains the parameter to an int
@page "/Product/{id:int}"

// this (without the constraint) would fail
// (unable to cast the value to an integer)
// @page "/Product/{id}"

<h1>Product Details for @Id</h1>

@code {
    [Parameter]
    public int Id { get; set; }
}